Tsunami Records in Sediments: A Seminar by Dr. Katrin Moeneke

The Geoscience Department presents a seminar by Dr. Katrin Moeneke, U. Pitt. Johnstown, on Friday, October 23, from 12:15 to 1:15 p.m. in Walsh Hall, room 104. Her seminar, “Coastal Marshes in Northern Sumatra as an Archive for Past Tsunamis,” will discuss her work on understanding the recurrence of tsunami in Northern Sumatra.

Abstract: The 2004 Sumatra-Andaman earthquake and following tsunami were unprecedented in Aceh, the northernmost province of Sumatra. In this study, we use buried sand sheets on a coastal plain to extend tsunami history 1,000 years into Aceh’s past. The 2004 tsunami deposited a sand sheet up to 1.8 km inland on a marshy beach ridge plain. Sediment cores from these coastal marshes revealed two older extensive sand sheets with similar sediment characteristics. These sheets, deposited soon after AD 1290-1400 and AD 780-990, probably represent earlier tsunamis. An additional sand sheet of limited extent might correlate with a documented smaller tsunami of AD 1907. These findings, a first step towards a paleotsunami record for northern Sumatra, suggest that damaging tsunamis in Aceh recur infrequently enough that entire human lifetimes can elapse between them. Such recurrence adds to the challenge of preparing communities along the northern Indian Ocean shorelines for future tsunamis.

This seminar is part of an ongoing Geoscience Seminar Series that occurs most Fridays from 12:15 to 1:15 in Walsh Hall, room 104.

For further information regarding this event and future seminars, please contact the Geoscience Department at 724-357-2379.